The world is relying on a UK drugmaker with limited experience in crafting vaccines to help fight the pandemic, and AstraZeneca's stumbles are delaying its response

• AstraZeneca had been "slow" to provide American drug regulators with vaccine data that led to delays in completing late-stage trials, The New York Times reported.
• The biopharmaceutical company's missteps have cost the country time to review trial data. AstraZeneca decided to restart clinical trials after scientists pointed out inconsistencies in the first trial analysis.
• The Trump administration bought 300 million doses of AstraZeneca's vaccine for $1.2 billion, despite the fact the company had little experience developing vaccines.

The US made a big bet on AstraZeneca and Oxford's COVID-19 vaccine.

But the European biopharmaceutical firm's failure to quickly provide the US Food and Drug Administration with trial data proved the risky bet may have fallen flat, according to a new report by the New York Times.

The US had given AstraZeneca, which had little experience developing vaccines, $1.2 billion to secure 300 million doses of the drugmaker's vaccine back in May. The Trump administration had hoped the FDA would green light AstraZeneca's vaccine in time to get Americans the first doses by October 2020.

But the expectations fell short when AstraZeneca announced in November it would restart clinical trials after scientists pointed out inconsistencies in the first trial analysis.

AstraZeneca announced it halted trials on September 6 after a UK participant fell ill with what could have been an adverse side affect to the vaccine.

The UK and Japan had deemed the trials safe to resume well before the FDA did because AstraZeneca had been "slow" to provide American regulators with trial data, the Times reported. Multiple FDA officials told the Times AstraZeneca had not even notified the trial had paused.

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AstraZeneca's missteps cost the country time to review the trial data and approve a safe vaccine. The FDA will likely approve vaccines developed by pharmaceutical firm Pfizer and biotech company Moderna in December to begin immunizing healthcare workers and long term care facility residents.

But the Pfizer and Moderna vaccines require 2 doses, limiting the number of Americans who can get shots. Plus, Pfizer's vaccine requires transportation and storage in ultracold freezers. AstraZeneca's model, however, is easier to store and cheaper to buy.

The US had planned to vaccinate 20 million Americans before the end of the year, but Army Gen. Gustave Perna, who heads federal vaccine delivery, decreased the target number of initial shipments of Pfizer's vaccine from 6.4 million to 2.9 million this week.

Though the US bought 100 million doses of the Pfizer vaccine, the country passed up the opportunity to secure more shots this summer. The decision will likely mean the drug maker will not get the US additional doses until July 2021 due to commitments to other countries, The New York Times reported.

Business Insider has reached out to AstraZeneca for further comment.